Happy Sunday! Welcome to the last installment of this weird babysitter AU that really didn't have very much to do with babysitting. I hope you enjoy~! =)

Disclaimer: I do not own any of the characters in this work. All characters belong to Disney/Marvel.

"Burning the midnight oil, Mr. Hamada?"

Tadashi blinks over his computer screen, his fingers pausing on the keys. The hallway outside his office is dark and his eyes are out of focus from staring at his monitor all night, but he can easily make out Doctor Callaghan's figure standing just outside his door. Despite how tired and weary he is from calculating the end of the semester grades (why are his students so bad at making paper deadlines?), he can't stop the genuine smile that stretches across his lips at the sight of his older colleague.

"As are you, Professor," he responds, pushing his chair slightly to the side so that he can see him more clearly.

His old mentor laughs, stepping into the room. His charcoal gray slacks crinkle slightly when he walks, their hems pushing against his dark brown oxfords. "I was just leaving when I noticed your light was still on. You're a bit young to be spending your Friday nights here."

"I'm not as young as I used to be," Tadashi sighs a little wistfully. He rolls his shoulders as he speaks; he can feel his words in the way his scapula pops uncomfortably against his spine.

"It's a little early to be saying that," Doctor Callaghan smiles, crossing his arms good-naturedly. "You're not even thirty yet, are you?"

"Not quite. Just a few more months until the big 'three oh,'" Tadashi grimaces. He's not looking forward to it. He's never really thought about age as a limit, but he's always been under the impression that he would be a little farther along in life by the time he was thirty. And while he has his dream job and he absolutely loves it, he's always just assumed he would have a family by now— maybe not a child, but at least a significant other to spend the holidays with. He shakes his head minutely at the thought; like Cass would ever let him miss out on her holiday feasts.

Besides, Hiro fills the void fairly well. Too well, if he's being honest with himself.

He seldom is.

"The big 'three oh,'" Doctor Callaghan reiterates with a chuckle. "What I wouldn't give to be that young again— I'm over twice that now. The big 'six five,'" he shakes his head and Tadashi can feel the flush settling on his cheeks. Sometimes, it's easy to forget that Robert Callaghan is as old as he is, especially with the way he moves around like a man half his age. His hair is solid gray and his face is a mix of wrinkles and laugh lines, but his eyes are just as sharp as one would expect from the man who reshaped the robotics industry. "Well, anyway, it's time for this old man to be getting home. You should do the same, Mr. Hamada."

"I'll be out in a bit," Tadashi smiles, leaning back in his chair. "Have a good night, Professor."

"You do the same," he responds, turning on his heel to retreat through the open office door. "Oh, and send Mr. Takachiho my congratulations."

"Hiro," Tadashi questions, tilting his head to the side in confusion. "Congratulations for what?"

Callaghan stops at the threshold into the hallway, turning back to him with one eyebrow raised. "About the job offer from Krei Tech," he explains. "It's not every day that someone his age gets an offer to run a branch overseas. He really has pushed the boundaries of robotics during his time here."

"Oh," Tadashi says dumbly, tapping his fingers against the top of his desk. He doesn't remember Hiro telling him anything about applying to work at Krei Tech, and he knows Hiro hasn't told him about being offered a job there. Overseas? Where overseas? Would he be far away or still close enough to visit? Tadashi doesn't know, and not knowing makes his heart sink into his gut. "I'll be sure to tell him then."

His lips stretch themselves into a stiff smile that immediately falls off his face when Doctor Callaghan turns away and begins his journey back down the hall. He glances at the clock on the wall— ten twenty-three already— and then towards his computer monitor where half a dozen spreadsheets are carefully arranged, with each of his students' names and grades listed alphabetically according to their class. He blinks at it, his fingers resting just over the keys, and he instantly knows that he won't be getting any more work done tonight because—

Hiro.

Hiro might be leaving— is probably leaving because no one turns down an offer from Krei Tech— and he hasn't talked to him about it.

Was he even planning to? Was Hiro going to tell him at all or was he just going to leave? Hiro's always been a free spirit. He's always done what he wanted to do, with or without anyone else's approval, and Tadashi wouldn't put it passed him to leave without a word. But, they've been in each other's lives for nearly thirteen years now. Tadashi's watched him grow up, and he's never once thought of the possibility of Hiro not being around, of him not being here in San Fransokyo where he can keep an eye on him. Tadashi's never thought of Hiro not being within arm's reach, just a phone call away.

And what if something happened to him while he was overseas? What if he got sick or hurt? Would he have anyone to call that was nearby? Anyone to take care of him? Hiro's almost an adult now— seventeen years old and more than proud of it— but he's never been the best at making friends and the idea of Hiro all alone in some new place is almost enough to send Tadashi into a panic.

He's far more attached to Hiro than he ever wanted to be.

The realization is more than a little horrifying.

Tadashi shakes his head at the thought, letting out a long sigh as he pushes back his chair and runs one of his hands down the side of his face. He's tired and he knows that he shouldn't be thinking about such things right now. He'll talk to Hiro about it the next time he sees him, and if Hiro wants to leave San Fransokyo, he'll do his best to help him plan and prepare even if he doesn't want him to leave. Because that's his job. He is the babysitter turned friend who needs to make sure that Hiro's happy. And if being here no longer makes him happy, then Tadashi will just have to wish him the best.

With that in mind, he saves his progress and shuts down his computer before grabbing his things and locking up his office for the night. It's late and Doctor Callaghan is right; he needs to go home. Quietly, he makes his way out of the building, the chilly spring air biting at his skin through his cardigan and clearing the fog that's settled in his head.

The San Fransokyo Institute of Technology campus is both eerie and gorgeous at night. The tall buildings let off a metallic glow that causes the normally luscious green grass to appear brown and distorted. The numerous hills that litter the property seem to cause the concrete path to wind on endlessly at night, snaking in each direction and moving from building to building.

Over the last several years, Tadashi's heard many of his students complain about being stuck on campus after dark, but he's never quite understood them. He loves the silent walk to his car each night when the lights are out and the city around the property is nothing but background noise. He loves the sound of his shoes hitting the red wooden bridge over the pond at the center of campus, the way it echoes in his ears with the water streaming on below. He even loves the way the windows let off that mirror-like sheen in the darkness, their lights long since snuffed out.

Except…

Tadashi stops outside the Ito Ishioka Robotics Lab, his lips pulling downward into a light frown. The building itself is a sleek dome that glows like the rest of the campus' buildings, eerie and blue and metallic, but there's a light on in one of the offices in the back. He can just barely see it from his position on the sidewalk outside— and he realizes with a start that the light is coming from his lab space. He doesn't use it as often as he used to because teaching has started to take up more of his time than he ever expected it would, but he has years of work in there. His original Baymax prototype is in there, tucked away in the corner as a just in case, and his blood suddenly runs cold.

He rushes into the building, his bag banging against his side as he runs up the steps and pushes through the door. It's unlocked because students often need to get into the lab late at night, but the faculty labs are supposed to require an access key to open them and he's sure his is securely tucked away inside his bag. He rounds the corner, his high-tops sliding against the tile and knocking him slightly off balance as he grabs at the door to his lab. The little keycard receptacle is flashing green, meaning that the door is unlocked and anyone can be inside and—

Tadashi surges through the door.

He's greeted with the most undignified yelp he's ever heard and the sound of a body hitting the floor. A rolling chair rams against the wall and big brown eyes pop up over the table in the center of the room. His breath catches in his throat.

"You—," Hiro gasps, pushing himself up on his elbows, "You nearly gave me a heart attack! What the hell was that?"

Tadashi blinks at him. And then he laughs, long and hard, because it's nothing. Nothing's wrong. It's just Hiro. Hiro who's looking at him like he's lost his mind, those doe brown eyes of his slightly narrowed, his mop of black hair held out of his eyes with a laughable assortment of bobby pins. If not for those, he would look all grown up now; it's a sobering thought. "You gave me the heart attack. It's the middle of the night! I saw the light on up here and I thought— I thought someone was trying to steal Baymax again."

"No," Hiro winces, biting the inside of his cheek. He glances at the corner of the room where Baymax's portable case lies, peaceful and undisturbed. It's a wonder he didn't wake him when he fell. "It's just me."

He sighs, leaning back against the wall. His arms cross over his chest, "What are you even doing here? And how exactly did you get in here?"

There's a short pause between them where Hiro's fingers twist guiltily around the sleeves of his hoodie and his cheeks burn bright red. Tadashi's chest constricts at the sight.

"I may or may not have made a copy of your access card at the beginning of the semester while you were sleeping," Hiro breathes, smiling sheepishly at him over the table. The flush in his cheeks rises to paint his ears, just barely visible where the pins hold his hair back.

Tadashi lets out a shaky exhale, running a hand through his hair, an easy smile turning up the corners of his lips to let Hiro know that he isn't mad. It's a blatant disregard for school policy and it could easily get Hiro expelled, but he's graduating tomorrow and Tadashi… He's never been able to stay mad at him— for anything. "That still doesn't explain what you're doing here."

Hiro shrugs, "Nothing really." He grabs the chair that rolled into the wall and takes a seat, pulling his legs up to sit with his legs crossed underneath him. Tadashi wants to tell him that that is not the correct way to sit in a chair, but— Hiro's not a child anymore. He needs to stop coddling him so much.

He doesn't want Hiro to resent him.

"Nothing," he mimics with a little lilt at the end. "Doesn't look like nothing." And it doesn't, not with the way that Hiro looks away from him, gazing out the window that reveals nothing but the darkness of the campus and the faded lights from downtown San Fransokyo in the distance.

"It's really nothing, Tadashi," he reiterates. He carefully maneuvers one of his legs up so he can rest his chin on his knee. For a moment, he continues to stare out the window, but then he turns and those big brown eyes of his are looking straight at him. All at once, Tadashi realizes just how grown up Hiro really is. He's still lithe and scrawny, with skinny shoulders and round cheeks, but his eyes show a confidence and a steadiness that he's never really noticed before. They still have that spark— the light of creativity that he knows he'll never grow tired of seeing— but the childlike wonder of the four year old he once knew is gone. Hiro no longer has the eyes of a child. "I'm just thinking."

"Thinking," Tadashi questions, pushing himself off the wall to walk closer to the table. He leans against it; the surface shifts just slightly under his weight. "Want to tell me what about?"

Hiro shrugs again, tilting his head back to gaze at the ceiling. The chair rolls minutely as he moves. "Nothing important."

"So, let me get this straight," he rests his head on his palm, "You're sitting in my office— which you're not supposed to be in— in the middle of the night, doing nothing and thinking about nothing important. Uh huh. I don't buy it." Hiro looks back at him and Tadashi lets out a sigh, his shoulders sagging. "Thinking about the offer from Krei Tech, perhaps?"

Hiro makes a face at him, his nose scrunching up ever so slightly, "You heard about that?"

"Yeah," Tadashi breathes, his lips pulling themselves into a light frown of their own accord. So Hiro really hadn't been planning on telling him at all. "Doctor Callaghan sends his congratulations."

"He would."

"From what I heard, it's a great opportunity." His words come out bitter without him meaning them to. He shakes his head and swallows passed the lump in his throat. No. This is for Hiro. He needs to be supportive. "So, where will you be stationed?"

"Where will I be stationed," Hiro questions. Doe brown eyes blink at him before his lips set themselves into a tight scowl. "Nowhere. I already declined the offer."

Tadashi nearly chokes on his relief. "You declined it?"

"Yeah," Hiro responds plainly, twisting so he's sitting correctly, both of his feet firmly planted on the floor. "I mean, yeah— running the Hokkaido branch would probably be pretty cool but— it'd also be pretty miserable too, you know? I like it here and Aunt Cass would miss me and, well, you're here too, so there's really no reason for me to leave, right?"

When he finishes, his face is painted an alarming shade of red and his knuckles are white from the force of his grip on the bottom of the chair. And he's looking right at him, those big brown orbs of his staring at him with so much sincerity that Tadashi just melts.

When Honey Lemon first told him that Hiro had a crush on him, Tadashi was horrified. It was inappropriate; he used to be his babysitter. And on top of that, there were nearly twelve full years between them and Tadashi didn't think that that sort of age difference was healthy, not when Hiro should have technically still been in high school at the time.

To prevent Hiro from liking him further (and to prevent himself from giving in because he's never been one to deny Hiro anything), Tadashi tried to set certain boundaries between the two of them. Whenever they went out, someone else accompanied them. Hiro wasn't allowed to stay at his house over the weekend unless Tadashi could convince someone else to stay too. But he was too obvious about it— and his boundaries ended up hurting Hiro way more than they were helping him. Tadashi hadn't been able to bear it. He'd ended up just hoping that it went away on its own.

But it didn't.

And Hiro's feelings had just grown more and more obvious over the last two years.

Which is fine because they're harmless, but not fine at all because Tadashi's found himself liking them far more than he should.

He's always been attached to Hiro. Always. It wasn't until recently that he realized just how much.

He knows that a relationship between the two of them would still be inappropriate on so many levels, but he can recognize the fact that Hiro isn't the same four year old child he used to babysit anymore. He's still young— too young— but he's smart enough to make his own decisions. And over the last year, after Hiro shot up those last couple of inches and started pushing his hair out of his face, Tadashi's found himself wishing that Hiro's little crush wouldn't just disappear.

He's found himself wishing that maybe— maybe, just maybe— the two of them could actually be together, that they could be a couple.

But he knows it's wrong; he has to show self-control.

"Yeah," Tadashi coughs in an attempt to hide the fact that his heart is lodged somewhere in his throat. "I'm here."

"And you're not planning on leaving, so there's no reason for me to leave either," Hiro nods to himself, tilting his head downward to stare at the porcelain tiles on the floor. He scuffs the toe of his shoe against one of them; a faint squeak follows.

"That's not—," he swallows thickly, running his hand through his hair. "You shouldn't limit yourself because of me. There's a whole world out there."

Hiro's shoulders hunch inward. A long stretch of silence passes before— "Do you want me to leave?"

He sounds small; Tadashi's gut twists. "That's not what I meant. I just don't want you to miss out on anything by staying here for my sake."

"It's not really for your—," he makes an exasperated sort of noise, pushing himself out of the chair and coming to stand on the other side of the table. He's still shorter than Tadashi by several inches, but they're closer to eye to eye than they've ever been, with Hiro leaning over the table and glaring at him, those doe brown eyes of his squinted. "You just don't get it," he says.

Tadashi swallows. "I don't—"

"I like you."

He blinks. This is not what he wants. If Hiro stays silent, Tadashi doesn't have to acknowledge it. He doesn't have to be the adult that hurts his feelings. He doesn't have to do something he doesn't want to do. "Hiro, I—"

"No," Hiro cuts him off again, pushing against the table with his palms. "I like you. I fucking love you— have been in love with you for years— and I know you know. And I think— I think you like me too and you just won't admit it."

Hiro juts his chin out in defiance, those big brown eyes of his still staring straight at him. And Tadashi doesn't know what to say. He knows he needs to shut this down because it's gotten too far already and he needs to be the adult— and he wishes Hiro didn't push his hair back with those stupid bobby pins because this way he can see all the stubbornness and determination in Hiro's eyes and he doesn't know how to put a stop to this.

He doesn't know if he wants to.

"Tell me I'm wrong," Hiro demands, leaning impossibly close, his pelvis grinding against the table. "Tell me you want me to take the job in Hokkaido, that you want me to leave."

"Hiro—"

"Tell me that's what you want and I'll do it. I'll leave San Fransokyo and I won't bother you anymore."

"This really isn't—"

"Tell me."

"I—," Tadashi sighs and he can feel Hiro's breath ghosting across his lips. He can see the way his endless eyelashes frame his eyes, the way his jaw tightens. And it hits him. For all Hiro's confidence and airs, he's scared. He's scared that Tadashi's going to tell him he's got it all wrong. He's scared of being rejected. And Tadashi knows instantly that he's lost this battle. He's never been one to deny Hiro anything; it's too late to start now. "I don't want you to leave," he swallows. "I want you to stay right here."

"With you," Hiro adds, his lips ghosting over Tadashi's, just barely there.

"With me," he affirms. The words feel liberating with the way they lighten the tension in his shoulders. Because his secret it out. He likes Hiro; he loves Hiro.

It's inappropriate and wrong and—

"Good."

Chapped lips press against his own— firm and inexperienced and confident. And suddenly, everything is Hiro. Just Hiro. His eyelashes tickle Tadashi's cheek and his nose bumps against Tadashi's own. One of his hands comes up to tug at the collar of Tadashi's shirt, pulling him down so he can catch his lips at a better angle. The position is uncomfortable with Tadashi's hips pressing into the table's edge and Hiro pulling him down by his neck, but something about it feels right. He doesn't want it to stop.

Hiro's lips move away with a horribly empty sort of sound and those beautiful brown eyes of his stare right at him. They're both breathless, even though the kiss only lasted a few precious seconds, but Tadashi instantly leans forward, pressing their lips together one, two, three more times, with chaste little pecks that fill the vacant space between them.

It's Hiro who pulls away completely, twisting just slightly so his face is out of reach. The smile that stretches across his lips is breathtaking; Tadashi wonders why he's been denying it for so long.

"Was that so hard," Hiro asks, teasing and light and the same Hiro that he's used to. The same Hiro that worries him like crazy and makes his heart melt in his chest.

Tadashi doesn't respond. He knows he doesn't need to; Hiro already knows he's won. He always does.

And for once, Tadashi really doesn't mind.

And that's the end. It took him thirteen years, but at least Tadashi finally figured it out, yeah? (B̶u̶t̶ ̶r̶e̶a̶l̶l̶y̶,̶ ̶w̶h̶y̶ ̶y̶o̶u̶ ̶h̶a̶t̶e̶ ̶m̶e̶,̶ ̶H̶i̶r̶o̶?̶ ̶A̶l̶l̶ ̶I̶ ̶w̶a̶n̶t̶ ̶t̶o̶ ̶d̶o̶ ̶i̶s̶ ̶w̶r̶i̶t̶e̶ ̶y̶o̶u̶.̶ ̶)

This isn't quite what I originally planned for the end of this, but after spending weeks on it, rewriting it multiple times, and editing it over and over again, it's kind of grown on me. I just hope it didn't end up disappointing any of you guys.

Because, really? You guys are awesome for sticking with this. I'm really glad that so many of you have enjoyed reading this series. And also, thank you. Thank you for reading and thank you for all the lovely reviews. I really appreciate it.

Production: Since this is done, I'm going to start working on some other projects. Currently, I have a few one-shots planned, as well as three or four chapter stories that I'm trying to plot out. Hopefully, it won't take me very long to get started on something new.

Reviews are welcomed and responded to! I'd love to hear your thoughts!